Run antivirus and check only my PC disks[C:/ , D:/] or all disks incl

Depends how suspicious of malware you are. I occasionally scan external drives too especially if they were connected to somebody else's computer.
Any USB memory stick that was in a computer of my own I check first by using a Live Linux to boot from.

agphotoworld said:

Run antivirus and check only my PC disks[C:/ , D:/] or all disks including external ones like J:/ ???

Please note, the backslash \ is used in the "path" with drives in or connected to the computer while the forward slash / is used in the Addresses/URLs on the Internet, makes a big difference.

I have 2 USB HDDs connected to my main computer and 2 NAS storage drives connected to my Router and let Windows Defender do its default things. WD will check the NAS drives particularly when doing file management and has caught a few Trojans that came from backups of clients' computers. I do the backups by Mapping the Public Folder on those 2 drives and Copying to a Folder identified with each client as needed.

If you suspect malware, I recommend going to Virus, Trojan, Spyware, and Malware Removal Help Forum - BleepingComputer.com.

There aren't many users here, that I'm aware of, that can safely use FRST or other tools for malware removal.

zbook said:

Who can run commands to fix findings in Farbar?

If indicated then it could be run?

Suggest you consult @Jacee - she was a Microsoft Security MVP for many years, and has cleaned many systems for people over at SevenForums for a long time.